Sheldon Silver was sentenced to 12 years in prison Tuesday, making the former New York Assembly speaker one of the most powerful politicians in the state to be given time behind bars.

U.S. District Judge Valerie Caproni, who also ordered Mr. Silver to pay a fine of $1.75 million and forfeit about $5.3 million he reaped from the criminal schemes of which he was convicted, said she hoped the punishment would serve as a deterrent.